Method and apparatus for transmitting intelligence by radio waves



March 1952 w. w. CARGILL, JR

METHOD AND APPARATUS FOR TRANSMITTING INTELLIGENCE BY RADIO WAVES 5 Sheets-Sheet 1 Filed Aug. 3, 1945 MUCH-CUNN- UMDF MWDNOUNM mus-h.

INVENTOR ATTORNEY NZOIL OMUZL 59.8mm mats b 'VVJLLIAM W EAEEILZ. Jan

BY ((91% L EUOMOUMI ND DP March 11, 1952 w w, CARGlLL, JR 2,588,380

METHOD AND APPARATUS FOR TRANSMITTING INTELLIGENCE BY RADIO WAVES Filed Aug. 5, 1945 3 Sheets-Sheet 2 q INVENTOR F WILLIAM W: EAEEILL JR W L) ATTORNEY Marh 11, 1952 w. w. CARGILL, JR 2,588,380

METHOD AND APPARATUS FOR TRANSMITTING INTELLIGENCE BY RADIO WAVES 3 Sheets-Sheet 3 Filed A 3. 1945 INVENTOR WILLIAMW. CAEEJLLJIE ATTORNEY Patented Mar. 11, 1952 METHOD AND APPARATUS FOR TRANSMIT- TING INTELLIGENCE BY RADIO WAVES William W. Carg-ill, Jr., Madison, Wis. Application August 3, 1945, Serial No. 608,801

Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) This invention relates to amethod and apparatus for transmitting intelligence by radio waves. The principal object of this invention is to save time in radio transmission and to provide for the transmission of any message in as little as one ten-thousandth of the time normally required to speak the same message.

At present, as far as is known, it requires the same time to transmit a radio message as it does to speak the same message.

' Other objects of the invention are to enable such apparatus to send a greater volume of trafiic than other known existing units, and to provide an element of military security, inasmuch as it is extremely unlikely that any such message sent in accordance with the present invention could be detected by the enemy. In case of detection, it is unlikely that the enemy could detect the locationiof the sending station since time is not available to make a radio fix with such a short transmitting time; and if the sending station were located, it is highly improbable that the enemy could unscramble or decipher any message sent in the manner contemplated herein.

and separating that message into an arbitrary number of equal parts. After this has been done, each part is sent simultaneously with the others,

thereby reducing the time for sending the whole message to that of sending one part.

It can be seen that if a recording of a message .has its speed doubled when played into a radio transmitter, it requires but half the time to .transmit'it by radio as .it did to make the recording.

In a like manner, if a recording is played at normal speed, but has two pickup devices each taking half the message simultaneously, then the time required for radio transmission, with a separate transmitter for each pick-up, is one-half the time required to make the recording.

If then, as in this case, both methods are used,

the transmitting time is one-quarter of the original recording time. This time reduction corresponds directly to the speed ratio and the num-' ,ber of pickups.

In accomplishing these and other objects of the present invention, I have provided improved details in the structure of the apparatus and improved steps in the method, the preferred form paratus embodying my invention.

Fig. 2 is a more detailed diagrammatic view of fcorder.

an illustrative tube recorderand tube retainer. Fig. 3 is a detail fragmentary vertical crosssectional view of the forward end of a cathode ray tube embodying this invention.

Fig. 4 is a detail fragmentary elevational view showing the individual plates.

Fig. 5 is an enlarged detail vertical crosssectional view of an individual plate and its relation to a common plate. Referring more in detail .to the drawings:

In Fig. 1, there is shown a microphone I, the output of which is applied to 'a wire recorder 2. The wire in recorder 2 is so stored that there are accessible along its length ten points to which pickup units 3 may be applied to the wire. These points are spaced an equal distance alongthe length of the wire, so that when the recorder 2 is played back, the first pickup in line will receive the first tenth of the recorded message, and simultaneously the second pickup will receive the second tenth, and so on. Thus, when the recorder 2 is played back, it is necessary to run it through only one-tenth of the distance it ran when the message was applied by the microphone.

In practice it is preferred to play back the recorder 2 faster, for example, ten times faster, than the speed at which it was operated during recording of the message. Thus the total time required for playing back the wire recorder ,2 to apply the message to the ten pickups 3 is only one one-hundredth of the time required for the microphone l to apply the message to the re- This is because the recorder is played back through only one-tenth of the original distance, and it is run ten times faster.

Each pickup 3 applies its message to its respective tube recorder 4, which acts in the same manner as the wire recorder 2 in receiving, holding and relaying the message. The tube recorders 4 are capable of accepting the highly accelerated signal produced by the wire recorder 2. Upon completion of this acceptance, each tube recorder 4 then delivers the signal which it received to ten subordinate tube retainers 5. This makes a total of one hundred tube retainers 5, or ten for each tube recorder 4. At the same time, the tube recorders 4 speed up the transmission of the signal at the ratio of ten to one, for example, over that at which it was received. When all tube retainers 5 have received their signal, they all simultaneously feed their signals into separate transmitters 6, one or more transmitters for all tube retainers, are desired. These signals are then sent out on the air by means of a conventional an tenna 1.

Reference is now made to Fig. 2. It will be sufiiciently clear to understand the invention','

since the circuits supplying the tube recorders are similar and, in like manner, the circuits supplying the tube retainers are also similar.

The tube recorders 4 and the tube retainers 5 are similar to conventional cathode ray tubes,'ex-- cept in the present omission of the conventional fluorescent screen for receiving the cathode ray. I have substituted plates 8 and 9 for the screens to be used for the reception of the cathode ray beam..

' In 3, It! generally designates the forward partfof the cathode ray tube. This tube preferably includes a conventional glass envelope, without the usual fluorescent screen, but inits place, the condenser plates I l and I2 .are provided. Each condenser plate consists of first, a plurality of. common plates .1 I, in this instance ten, nearest what would normally be the fluorescent screen. The condenser plates have leads to a multi-post terminal '1, as indicated. Next. a gas dielectric of low pressure is provided in the space l3and finally the assembly I2 of individual plates l4. are provided nearest the cathode, not shown, of the tube..

In Fig. 4, the individual plates l4 facing the cathode ,of the tube I are shown. These plates are preferably arranged in groups in rows parallel to'each other.

An individualplate 14 of these groups is shown inF'i'g. It contains first, the individual plate. Centrally arranged in the upper part of the plate is an insulator [5 in the center of which is provideda connection I5 to a common plate I 1. Immediately between the plates l4 and the-common plate ll lies the gas or dielectric.

Particular attention should be given to the round insulator [5 in the upper part of the individualplates M. It should be noted that this insulator is preferably cup shaped with its apex pointing toward its common plate H. At the center of the apex of the insulator, protruding through it, is the metallic connection Hi to the common plate. On the side of the insulator,

which is toward thecommon plate II, in the dielectric, is deposited a very thin film IT, for example one or two molecules, of conductive materiaL. however, of a relatively resistant nature.

The operation of these plates I4 is as follows: The cathoderay developed in the tube. H] deposits-0n the lower portions of the plates M a certain number of electrons. These electrons act in a manner similar to those gathered upon any plate'in any ordinary condenser. They repel a. corresponding number of electrons from the commonplate H to the rear thereof. Inasmuch as there is a recess in the individual plates [2 which isrepresented by the interior of the cupped insulator 15, this recess will then have an electrostatic-charge in proportion to the number of ,electronson the plate l4. Therefore, as a con- .stantbeam of electrons is aimed at the center trons originally depositedupon the lower part of the plate. .Bearing this-in mind, it can then be seen that as a cathode-ray beama-sweeps-the in-- dividual plates in a scanning manner, and also if the beam varies in intensity, and scans below the insulator recesses of each plate, then each separate plate receives the corresponding amount of charge relative to the intensity of the beam at the instant it crosses the plate. Therefore, each plate bears a varying charge, plus or minus, relative to thatof its neighbor plates. Then, after this is done, a beam of constant intensity sweeps the plates at their insulator recesses, and the electrons are received by the connection [6 to the common plate in proportion to the amount of chargeon each individual plate. In this way, the change of potential on the. common plate varies inversely as, the charges upon the individual plates. when the beam of constant intensity swept across the openings in the plates M. The electrostatic .chargefor each plate l lis dependent upon the number of electrons it gathered from the initial beam which was varying in intensity.

The tubes I!) described above are employed in the circuit of this invention in the manner illustrated inFig. 2 herein. The numeral 4 designates the use of such a tube as the tube recorder of Figs.

the vertical deflection plates of the tube recorder i. Simultaneously, a horizontal sweep circuit 22 is actuated to cause the beam in recorder 4 to sweep horizontally across the plate 8. Thebeam is thus swept, back and forth across the tube re- .corder. screen by virtue of the cooperative operation ofthe sweep generator 22. and the vertical step-generator 20. This operation is well known inthe artof television, and reference is made to that art for the required circuital details.

While the cathode beam is sweeping the plate 8, its intensity is being modulated by the grid 21, in accordance with .the signals received by the appropriatepickup .3 andfed to the grid through wires 25, and-26. Upon completion of the sweeping operation, which coincides with the time requiredforpickup 3 to receive. its assigned tenth of they message from therecorder 2, each of the ten.,tube. recorders A will .have retained on its screen .8. a given tenth of the original message.

The message stored in the recorders 5 is now ready, to .be. taken from the recorders and applied tothetube retainers 5,.of which there are. 10 to eachrecorder 4.

In Fig.2, itwill be seen that tube recorder 4 has, ten ,vertical rows of condenser plates, each v corders; L-exceptinsteadof having a plurality of rows of condenser plates, they haveonly one row. Upon completion of. storing of themessage in vthe. tub e recorders 4, the synchronizer l9 flips ,back-andtriggers another stepv generating circuit 2| and another horizontal sweep circuit 23. The cooperative operation of these circuits is similar to that of the circuits ,.2!1,and,22, respectively, exceptthat-circuits 2|. and 23 operate through a cycle,.at,anaccelerated rate, for example, ten, times asfast ,asthe .circuitsZO, and 22.

Actuation of the circuits 2| and 23 causes the beam in the tube recorder Lto again sweep the plate 8, this time with a constant intensity, for the purpose of taking off the message stored .on the plate 9. The first tenth of the message is applied to the first of the ten tube retainers 5, through the connection 28 by modulation of the grid of retainer 5. The beam of the tube retainer is caused to sweep across its plate 8 simultaneously with the sweep of the take-off beam in the tube recorder 4. Each of the ten tube retainers is placed in operation successively. Thus, as the take-off beam sweeps the top row of condenser plates M in the tube recorder 4, the first of the tube retainers 5 will sweep its beam synchronously, thereby storing the first tenth of the message retained on the tube recorder 4. As the second row of condenser plates It in the tube recorder 4 is being swept, the second tube retainer 5 will sweep its beam synchronously and store the second tenth of the message. The operation continues until the message has been entirely transferred from each tube recorder 4 to its ten tube retainers 5.

At this point the message has been divided into 100 parts, the first factor of ten being introduced by the ten tube recorders 4, the second factor of ten being introduced by the tube retainers 5, of which there are ten for each recorder. Furthermore, the messages have been applied with two accelerating steps, so that to run off each onehundredth of the total message takes only one one-hundredth of the time which was required to speak it into the microphone I, which was in turn only one one-hundredth of the time required to speak the entire message, since the message itself has now been divided into one hundred parts.

The message stored in the one hundred tube retainers 5 is now ready to be taken from them by another sweep of the beams, controlled by circuits 24, 29, and 30, this time at constant intensity, and applied to one hundred transmitters 5. This final take-off of the message may be done simultaneously from each tube retainer 5, if desired, this operation being controlled by the timing circuit 24.

Thus, when all transmitters are operated simultaneously, the message may be transmitted in one ten-thousandth the time required to speak the message into microphone I.

With such a brief transmission time, the transmitters may be greatly overloaded, and for this purpose there is provided a suitable energy storage circuit 32, in which energy may be stored until such time as the transmitter is triggered. During the final take-oif of the message from the retainer 5, a triggering circuit 31 applies the energy stored in circuit 32 to the transmitter 6 at the proper moment. Energy storage c rcuits, represented by the numeral 32 may be either inductive or capacitive in character, and are wellknown in the pulse transmission art.

The operation of the system constructed as described is generally, as follows:

The pulse generated by the synchronizer l9, Fig. 2, is a square wave output from a single kick multivibrator. The RC constants are chosen according to the duration of the message desired to be sent and with relation to the speed-up also desired. This pulse is first fed to the grid of the tube recorders 4, Fig. 2, acting as an unblanking pulse for this grid. The rise in voltage representing the first part of the pulse, trips oif the vertical step pulse generator 2!], for example, Fig. 2. This is a multivibrator, the input side of which is nonconducting and the output side of which is conducting. It generates square wave output. These square waves are sent through a peaker circuit,

then through the triode acting as a rectifier, thereby giving an output of positive peaked waves. These peaked waves continue to be generated until the end of the synchronizer pulse, at which time the synchronizer pulse actuates the vertical step 20, for example, return pulse. This is a square wave multivibrator producing a negative square wave with a very short time constant. The square wave with its corresponding peaked waves are impressed on the vertical step generator. The peaked waves actuate the lower part of the vertical step generator, through the tube having a condenser in the cathode circuit. This condenser is charged each time a peaked wave occurs.

When the condenser is fully charged for its vertical step pulse generator, it must be discharged for further use. At this point, the negative pulse generated by the vertical step return pulse generator is fed through an amplifier. It is amplified and inverted to a positive pulse. This is then fed to the grid of a gas filled triode. When the gas ionizes and the tube conducts, the plate potential of this triode is at practically ground potential. This plate is connected to the other side of the condenser and the condenser is eifectively grounded, and its charge is reduced to zero. When this charging voltage (increasing by steps) is applied. to the vertical deflection plate on the tube recorders, in conjunction with the horizontal sweep, the tube recorders beam scans the condenser plates. As this is being carried out, the signals received from the wire recorder are being sent on to all of the tube recorders. It is fed to the grid of the cathode ray tube. This effectively modulates the intensity of the cathode ray beam, and therefore, charges each one of individual condenser plates in proportion to the intensity of the cathode ray beam. Therefore, these indivi ual condensers act as retaining or storing agents for the signal. This fact then allows the acce erated signal to be held for a short duration of time.

The next objective is, as shown in Fig. 2, to transfer the signal from units 4. Each unit of the tube recorders 4 has a corresponding series of preferably ten tube retainers as indicated at 28. This effectively again sub-divides the signal on each of the tube recorders into ten separate units.

At the same time the speed of the sweep which takes the message oif the tube recorder 4 is accelerated to ten times the speed at which the message was applied to the recorder 4. There should be separate sweeps and separate steps, because they take place at a time immediately after step 20 and sweep 22 and also at an accelerated rate. The rate of speed at which the signal is taken from the tube recorders '4 is at the same rate of speed as that which is used in the tube retainers since the actions are taking place at the same time. The tube retainers for any given tube recorders are not swept with signals at the same time. signals are swept upon given tube retainers in the sequence in which they are taken from the tube recorders. This, therefore, neces sitates a timing unit 24 to blank out all the tube retainers except that which is directly concerned, and also a transferring circuit which transfers from one tube retainer to the next successively as they are required.

Upon the completion of sweep 23 and step 2 I, all tube retainers have received their corresponding parts of the signal. At this point, since it is later of all the tube retainers will have picked up the signal impr'essed upon individual plates M. The

functions of thesetubes are similar to those of the tube; recorders. with the exception that the second cathode ray beam, while being equal in:in-

in going from positive to negative trips off the vertical step. pulse generator of step 2%. Step 29 has a similar arrangement, and in addition, has an- RC circuit before the entire step generator.

This, is indicated as the synchronizer timer 24,

Fig. 2, in order to delay this step generator, and also the horizontal sweep, a proper amount of time to allow for prior circuits to perform their functions. Also, in both step 2i and step 29 the negative pulse generated by the vertical step return is fed back to the vertical step pulse multivibrator, with the express purpose of stopping this multivibrator when it is no longer needed; In the case of step 28 t 1e synchronizer pulse does this automatically when it goes from positive to negative at the end of the synchronizer pulse.

Briefly then, a message spoken into the microphone ti, Fig. 1, is recorded on the wire recorder 2. The Wire recorder is then accelerated tenfold; One-tenth of the original message is picked up by each of the pickups for transference to tube recorder units t. The tube recorders arethen accelerated ten-fold. From each of the tube recorders 4i one-tenth of the one-tenth of tially similar. to the present system may be provided withth'eparts thereof arranged in substantially reverse order.

While I have shown but one embodiment of my invention, it is susceptible to modification without departing. from the spirit of the invention. I do not wish, therefore, to be limited by the, disclosures set forth, but only by the scope of the appended claims.

The invention described herein may be manufactured and used by or for the Government of theU-nitedstates of America for governmental purposes without the payment of any royalties thereon or therefor;

I claim:

1. In an apparatus of the character described, first detecting means effective to receive a message to-be transmitted, a'first recorder responsive to said first detecting means and effective to retain the message, a plurality of second detecting means, each said second detecting means being effective to receive a predetermined part of t'ne. message; retained by said first recorder, apluralityofsecond recorders corresponding respectively tosaid plurality of second detecting means, each said second recorder being efiective to retain that part of the message received by its corresponding second detecting means, a pluralit y ofthird detecting means, each said third detecting means being effective toreceivea predetermined portionof the parts of the. message retained by said second recorders, and means for transmitting the portions of the message received by each said third detecting means;

2. The method of transmitting intelligence consisting of conveying. a message into a microphone, electrically recording the message, dividing the recorded message into a plurality of parts, transmitting each of said parts of the electrically recorded message at anaccelerated rate, electrically recording the respective parts of the acceleratedrnessage, dividing each of the recorded parts of the message into a plurality of portions, and transmitting each of said por-.

tions of the recorded parts of the message at a further accelerated rate.

3. In an apparatus of the character described, first detecting means eiiective to receive a messagetobe transmitted, a recorder responsive to said first. detecting means and efiective to retain the message, a plurality of second detecting means, each said second detecting means being effective to receive a predetermined part of the message retained by said recorder, and means for transmitting the parts or the message received by each said second detecting means.

i. In an apparatus of the character described,

' a microphone, a wire recorder for receiving a message impressed on the microphone, a tube recorder operatively connected with the wire recorder, a tube retainer operatively connected with the tube recorder, a trip interposed between the wire recorder and the tube recorder, a synchronizer interposed'between the trip and the tube recorder reactive to said trip, a horizontal sweepror acting on the energy produced in the tube recorder and retainer to effect scanning therein, a step for controlling the vertical position of application of said energy relative to said tube recorder and tube retainer, a synchronized timer for actuating the tube retainer in desired relation to the tube recorder, and means for transmitting signals impressed on the tube retainer.

5. In ann'apparatus of the character described, a condenser for a cathode ray tube comprising a plurality of plates each having an insulated recess, athin coating of conducting material on the outer bounding surfaces or said recess, said material being of resistive character relative to the material of the plate, a plate common to said fi'rstnamed plates, means connecting the individualplates to the common plate, and a dielectric between said plates.

XVILLIAM W. CARGILL, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,977,398 Morrison Oct. 16, 1934 2,191,565 Henroteau Feb. 27, 1940 2,219,021 Riesz Oct. 22, 1940 2,245,364 Riesz et a1. June 10, 1941 2,277,516 Henroteau Mar. 24, 1942 2,291,476. Kernkamp July 28, 1942 2,301,743. Nagy et a1 Nov. 10, 1942 2,312,897 Guanella 1 Mar. 2, 19513 2,406,353 Myers Aug. 27, 1946 

